Add WCAG Alt Text to Every Image with One API Call

If your site has images without alt text, you have two problems:

1. Screen readers can't describe them to visually impaired users
2. You might get sued -- ADA lawsuits over web accessibility hit record numbers in 2025

Manually writing alt text for hundreds of images is tedious. So I built an API that does it with one call per image.

The API

Send an image URL, get WCAG 2.1 compliant alt text back:

import requests

response = requests.post(
    "https://origrid-alt-text.p.rapidapi.com/v1/alt/generate",
    headers={
        "X-RapidAPI-Key": "YOUR_KEY",
        "Content-Type": "application/json"
    },
    json={"image_url": "https://picsum.photos/id/42/800/600"}
)
print(response.json())

Response:

{
  "alt_text": "Two teal coffee cups on saucers and a smartphone on a rustic wooden table in a cafe",
  "alt_text_length": 84,
  "wcag_compliant": true
}

That's it. No complex setup, no image upload, no training. Send a URL, get alt text.

What makes it WCAG compliant

The API follows WCAG 2.1 Success Criterion 1.1.1:

• Max 125 characters -- screen readers handle short alt text better
• Describes content, not decoration -- "sunset over beach" not "beautiful photo"
• Never starts with "Image of" or "Photo of" -- screen readers already announce it's an image
• Specific -- mentions subjects, actions, colors, and setting

The wcag_compliant boolean in the response tells you programmatically whether the generated text meets the criteria.

Real examples

Image	Generated alt text
Beach sunset	Golden sunset over sandy beach with turquoise waters and palm tree silhouettes
Coffee shop	Two teal coffee cups on saucers and a smartphone on a rustic wooden table in a cafe
Dog portrait	A black labrador puppy sits on a wooden floor, looking up with big dark eyes
Mountain landscape	Mountain lake surrounded by pine trees with snow-capped peaks reflected in calm blue water

All under 125 characters, all descriptive, all screen-reader friendly.

Bulk processing with Python

Here's how to add alt text to every image on a page:

import requests
from bs4 import BeautifulSoup

RAPIDAPI_KEY = "your_key"
HEADERS = {
    "X-RapidAPI-Key": RAPIDAPI_KEY,
    "Content-Type": "application/json"
}

def get_alt_text(image_url):
    resp = requests.post(
        "https://origrid-alt-text.p.rapidapi.com/v1/alt/generate",
        headers=HEADERS,
        json={"image_url": image_url}
    )
    return resp.json()["alt_text"]

page = requests.get("https://yoursite.com/page")
soup = BeautifulSoup(page.text, "html.parser")

for img in soup.find_all("img"):
    if not img.get("alt"):
        alt = get_alt_text(img["src"])
        img["alt"] = alt
        print(f"Added: {alt}")

Why not use ChatGPT directly?

You could, but:

1. ChatGPT doesn't enforce 125 char limit -- you'd need to prompt-engineer and validate
2. No wcag_compliant flag -- you'd build your own validation
3. API integration is messy -- ChatGPT's API isn't designed for single-purpose endpoints
4. Cost -- GPT-4 vision is expensive for bulk image processing

Origrid Alt Text is a purpose-built endpoint. One call, one response, validated output.

Try it

Origrid Alt Text on RapidAPI -- free tier (50 images/month), no credit card required.

Full API docs and test endpoint available directly on the RapidAPI listing.

---

How do you handle alt text at scale? I'm curious about CMS integrations people would find useful. Drop a comment.